Pickering Nuclear Generating Station

The reactors can be classified as follows:

PICKERING A

• PICKERING A 1 (Safe Shutdown state)
• PICKERING A 2 (Safe Shutdown state, defuelled)
• PICKERING A 3 (Safe Shutdown state, defuelled)
• PICKERING A 4 (Safe Shutdown state)

PICKERING B

• PICKERING B 5
• PICKERING B 6
• PICKERING B 7
• PICKERING B 8

File:Pickering Nuclear Generating Station construction 1965.jpg

The site was once Squires Beach located west of Duffins Creek. The facility was constructed in stages between 1965 and 1986{{Cite web |date=October 2008 |title=Better Never than Late: The Climate Fall-Out of Ontario's Nuclear Electricity Plan |url=https://www.pembina.org/reports/gp-betternever.pdf |website=Greenpeace Canada}} by the provincial Crown corporation, Ontario Hydro, with significant completion of Station A scheduled for 1971.{{Cite news |date=1967-04-05 |title=it seems like only yesterday this was a farmer's field |pages=5 |work=Canadian Champion (Milton, ON) |url=https://news.milton.halinet.on.ca/2497804/page/5?q=text%3A%28Gordon%20AND%20McIntosh%29&docid=OOI.2497804 |url-status=live |archive-url=https://web.archive.org/web/20200321133843/http://news.milton.halinet.on.ca/2497804/page/5?q=text%3A%28Gordon%20AND%20McIntosh%29&docid=OOI.2497804 |archive-date=2020-03-21}} In April 1999, Ontario Hydro was split into five component Crown corporations with Ontario Power Generation (OPG) taking over all electricity generating stations.{{Cite web |date=2017-03-09 |title=A look at the long, complicated history of Ontario hydro |url=https://www.yorkregion.com/news-story/7165441-a-look-at-the-long-complicated-history-of-ontario-hydro/ |url-status=live |archive-url=https://web.archive.org/web/20201112001708/https://www.yorkregion.com/news-story/7165441-a-look-at-the-long-complicated-history-of-ontario-hydro/ |archive-date=2020-11-12 |access-date=2020-05-13 |website=YorkRegion.com}} OPG continues to operate the Pickering station.{{cite web |date= |title=Pickering Nuclear Generating Station |url=https://www.opg.com/powering-ontario/our-generation/nuclear/pickering-nuclear-generation-station/ |url-status=live |archive-url=https://web.archive.org/web/20210423045528/https://www.opg.com/powering-ontario/our-generation/nuclear/pickering-nuclear-generation-station/ |archive-date=2021-04-23 |access-date=2021-11-29 |website=OPG |publisher= }}

The Pickering station is a large multi-unit nuclear facility, comprising six operating CANDU nuclear reactors with a total output of 3,114 MW when all units are on line, and two non-operating units with a total output of 1,030 MW currently shut down in safe storage. The facility is connected to the North American power grid via numerous 230 kV and 500 kV transmission lines.{{Cite web |date=2016-06-30 |title=Pickering-Ajax-Whitby Sub-region Integrated Regional Resource Plan - Appendices |url=https://www.hydroone.com/abouthydroone/CorporateInformation/regionalplans/gtaeast/Documents/2016-Pickering-Ajax-Whitby-IRRP-Appendices.pdf |url-status=live |archive-url=https://web.archive.org/web/20190224050150/https://www.hydroone.com/abouthydroone/CorporateInformation/regionalplans/gtaeast/Documents/2016-Pickering-Ajax-Whitby-IRRP-Appendices.pdf |archive-date=2019-02-24}}

The facility was operated as two distinct stations, Pickering A (Units 1 to 4) and Pickering B (Units 5 to 8) until 2011.{{Cite news|url=https://www.theglobeandmail.com/canada/article-ontario-government-supports-opg-proposal-to-operate-pickering-nuclear/|title=Ontario government supports OPG proposal to operate Pickering nuclear station past planned 2024 closing|newspaper=The Globe and Mail|date=16 January 2020|last1=McClearn|first1=Matthew|last2=Baum|first2=Kathryn Blaze|access-date=13 May 2020|archive-date=18 January 2020|archive-url=https://web.archive.org/web/20200118024000/https://www.theglobeandmail.com/canada/article-ontario-government-supports-opg-proposal-to-operate-pickering-nuclear/|url-status=live}} While primarily administrative in nature, the division was not wholly artificial, as there are some distinct differences in design between the two groups of stations. (Example: The Pickering A units employ a moderator dump as a shutdown mechanism,{{cite web |date=2016-04-08 |title=The Use of Rod-Based Guaranteed Shutdown State in CANDU Reactors |url=https://nuclearsafety.gc.ca/eng/resources/research/technical-papers-and-articles/2016/Use-of-rod-based-guaranteed-shutdown-state-in-candu-reactors.cfm |url-status=live |archive-url=https://web.archive.org/web/20211120190029/https://www.nuclearsafety.gc.ca/eng/resources/research/technical-papers-and-articles/2016/Use-of-rod-based-guaranteed-shutdown-state-in-candu-reactors.cfm |archive-date=2021-11-20 |access-date=2021-11-29 |website=Canadian Nuclear Safety Commission |publisher= }} a feature not found in Pickering B, which instead uses what is called an over-poisoned reaction guaranteed shutdown.{{cite web |author=Urjan |first=R. |date=2010 |title=Rod-Based Guaranteed Shutdown States (RBGSS) implementation at Pickering B (IAEA-TECDOC--1650) |url=https://inis.iaea.org/search/search.aspx?orig_q=RN:41126193 |url-status=live |archive-url=https://web.archive.org/web/20200609065617/https://inis.iaea.org/search/search.aspx?orig_q=RN%3A41126193 |archive-date=2020-06-09 |access-date=2021-11-29 |website=International Atomic Energy Agency (IAEA) |publisher= }}) There are, however, a number of systems and structures in common between the two stations; the most notable of these is the shared vacuum building, a negative pressure containment system.{{cite web |date=3 February 2014 |title=Pickering Nuclear Generating Station |url=https://nuclearsafety.gc.ca/eng/reactors/power-plants/nuclear-facilities/pickering-nuclear-generating-station/index.cfm |url-status=live |archive-url=https://web.archive.org/web/20211118171601/https://www.nuclearsafety.gc.ca/eng/reactors/power-plants/nuclear-facilities/pickering-nuclear-generating-station/index.cfm |archive-date=2021-11-18 |access-date=2021-11-29 |website=Canadian Nuclear Safety Commission |publisher= }} The operation of Pickering A and B was unified in 2010,{{Cite web |date=2014-11-20 |title=EB-2013-0321 - Decision with Reasons |url=https://www.oeb.ca/oeb/_Documents/Decisions/dec_reasons_OPG_20141120.pdf |url-status=live |archive-url=https://web.archive.org/web/20201216055835/https://www.oeb.ca/oeb/_Documents/Decisions/dec_reasons_OPG_20141120.pdf |archive-date=2020-12-16 |website=Ontario Energy Board}} to reduce costs now that Pickering A Units 2 and 3 are shut down in safe storage.

On December 31, 1997 the four Pickering A reactors, along with the remaining three units at Bruce A, were shut down by Ontario Hydro for safety reasons{{Cite web |last=CBC News |date=July 7, 2004 |title=Ontario to spend nearly $1 billion to restart nuclear reactor |url=https://www.cbc.ca/news/canada/ontario-to-spend-nearly-1-billion-to-restart-nuclear-reactor-1.508569}} and placed in lay-up. Specific to Pickering A, four years earlier the AECB had required mandatory upgrades to the safe shutdown system be completed by the end of 1997,{{Cite web |date=June 7, 2001 |title=Canada's Nuclear Reactors: How much safety is enough? |url=https://sencanada.ca/content/sen/Committee/371/pdf/interim-enrg-e.pdf }} which differed from that at the other three plants. Pickering A featured a moderator dump as its 2nd shutdown system,{{Cite web |title=CANDU Fundamentals - Reactivity mechanisms |url=https://canteach.candu.org/Content%20Library/20040723.pdf }} and this was deemed too slow compared to the poison injection system that later plants used, including Pickering B. Ontario Hydro committed to the refit and restart project, but it underwent long delays and large cost over-runs.

Often called a refurbishment, the return to service of Pickering A units 1 and 4 did not involve refurbishing the reactor cores, which involves replacing the calandria tubes, pressure tubes, feeders and end fittings. The main scope of work was the upgrading of the secondary safe shutdown system as well as some maintenance. Instead of retrofitting the poison injection found at the other plants, the least cost option was to add more shutdown rods and then split them into separate, independent groups. This was deemed sufficient by the AECB, despite acknowledging that this does not in fact constitute a fully independent fast acting secondary safe shutdown system.{{Cite web |date=June 7, 2001 |title=Canada's Nuclear Reactors: How much safety is enough? |url=https://sencanada.ca/content/sen/Committee/371/pdf/interim-enrg-e.pdf }}

Premier Mike Harris asked former federal energy Minister Jake Epp to study and make recommendations on the problems with the Pickering restart. The review panel was established in May 2003.

Unit 4 was refitted and then restarted in Sept. 2003. The election of the Ontario Liberal Party in October 2003 delayed action on the Epp report. In late 2003, the new government fired the top three executives of OPG for botching the Unit 4 restoration, which was years late and millions of dollars over budget.{{Cite news|url=https://www.theglobeandmail.com/report-on-business/opg-cancels-pickering-repairs/article1121297/|title=OPG cancels Pickering repairs|newspaper=The Globe and Mail|date=12 August 2005|last1=Luciw|first1=Roma|access-date=13 May 2020|archive-date=9 June 2020|archive-url=https://web.archive.org/web/20200609065623/https://www.theglobeandmail.com/report-on-business/opg-cancels-pickering-repairs/article1121297/|url-status=live}}

Mr. Epp and the Pickering A Review Panel released their report in December 2003,{{Cite web |date=December 2003 |title=Report Of The Pickering "A" Review Panel |url=https://collections.ola.org/mon/7000/10317476.pdf |url-status=live |archive-url=https://web.archive.org/web/20200609065624/https://collections.ola.org/mon/7000/10317476.pdf |archive-date=2020-06-09}} which acknowledged the large cost over-runs and delays, attributing blame to bad management. The Epp Review estimated the cost of restarting the remaining three reactors at $3 – 4 billion and supported the continuation of the project.

The government of Dalton McGuinty appointed Epp to the Ontario Power Generation Review headed by John Manley to examine the future role of Ontario Power Generation (OPG) in the province's electricity market, examine its corporate and management structure, and decide whether the public utility should proceed with refurbishing three more nuclear reactors at the Pickering nuclear power plant. The report recommended proceeding with the restart of Pickering “A” reactors 1, 2, and 3, sequentially. The report argued that the restart of units 2 and 3 would be contingent on whether “OPG will be able to succeed at the Unit 1 project."{{Cite report |first1=J. |last1=Manley |first2=J. |last2=Epp |first3=P.C. |last3=Godsoe |date=2004-03-15 |title=Transforming Ontario's Power Generation Company |url=https://inis.iaea.org/search/search.aspx?orig_q=RN:35041982 |publisher=The Ontario Power Generation Review Committee |language=English |pages=47 |via=INIS}}

The McGuinty government accepted the OPG Review Committee's recommendation and allowed the refit and restart of reactor 1.

The anti-nuclear group Sierra Club of Canada criticized the 2004 OPG Review Committee report for not attributing any blame to the problems of nuclear technology, noting that there were no energy or environmental experts appointed to the panel.{{cite web |date=2004-03-17 |title=Manley Expected to Support Pickering Nuclear Boondoggle |url=http://www.sierraclub.ca/national/media/item.shtml?x=603 |url-status=dead |archive-url=https://web.archive.org/web/20040416153146/http://www.sierraclub.ca/national/media/item.shtml?x=603 |archive-date=16 April 2004 |website=Sierra Club of Canada |publisher=}}

Numerous changes in executive-level staff and project management strategy were made for the follow-on project to refit Unit 1. The experience with the return to service of Pickering A Unit 1 was significantly different from Unit 4, with a much tighter adherence to schedule and budget.{{Cite web |date=2010-02-16 |title=OPG Moves to Planning Phase of Darlington Refurbishment |url=https://www.newswire.ca/news-releases/opg-moves-to-planning-phase-of-darlington-refurbishment-539310881.html |access-date=2022-06-08 |website=Cision Canada |language=en}} In August 2005, the OPG Board of Directors announced that Units 2 and 3 would not be returned to service due to specific technical and cost risks surrounding the material condition of these two units. Unit 1 was returned to service in November 2005.{{cite web |title=Ontario Supports Plan to Safely Continue Operating the Pickering Nuclear Generating Station |url=https://news.ontario.ca/en/release/1002338/ontario-supports-plan-to-safely-continue-operating-the-pickering-nuclear-generating-station |publisher=Government of Ontario |access-date=April 24, 2024 |date=September 29, 2022}}

{{wide image|Pickering-nuclear-generating-station-001.jpg|800px|The Pickering Nuclear Generating Station, viewed from the west. All eight reactors are visible, from 2.5km to 3.25km away.}}

The graph represents the annual electricity generation at the site (A and B combined) in GWh.

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bar:2019 from:0 till:23657

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text: Pickering Nuclear Generating Station

As of the end of 2023, the total lifetime output of the facility was 972,252 GWh.

Ontario Hydro estimated the construction cost for the four Pickering "A" units at $508 million in 1965. Actual cost was $716 million (in 1973 dollars).{{cite web |title=A Journalist's guide to Nuclear Power |url=https://inis.iaea.org/collection/NCLCollectionStore/_Public/23/059/23059658.pdf |access-date=3 May 2023 |website=inis.iaea.org}} Adjusted for inflation, the $508 million estimate in 1973 dollars is $698 million, a 2.6% overrun.

The 1974 estimated cost for the four Pickering "B" units was $1.585 billion. Final cost was $3.846 billion (1986 dollars).{{cite web |title=Appendix 2 - Ontario's Nuclear Generating Facilities: A History and Estimate of Unit Lifetimes and Refurbishment Costs |url=https://www.pembinafoundation.org/reports/appendix2.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170404155726/https://www.pembinafoundation.org/reports/appendix2.pdf |archive-date=4 April 2017 |access-date=19 April 2022 |website=www.pembinafoundation.org}} Adjusted for inflation, the $1.585 billion estimate in 1986 dollars is $4.082 billion, putting Pickering B under budget.

According to Ontario's FAO, the cost for refitting and restarting the Pickering A units deviated significantly from projections.{{Cite web |date=Fall 2017 |title=Nuclear Refurbishment - An Assessment of the Financial Risks of the Nuclear Refurbishment Plan |url=https://www.fao-on.org/web/default/files/publications/Nuc%20Refurb%20nov%202017/Nuclear-Refurb-EN.pdf |url-status=live |archive-url=https://web.archive.org/web/20210126122018/https://www.fao-on.org/web/default/files/publications/Nuc%20Refurb%20nov%202017/Nuclear-Refurb-EN.pdf |archive-date=2021-01-26 |website=FAO - Financial Accountability Office of Ontario}}

- Pickering Unit 4 was slated to cost $460 million and ultimately ended up costing $1.25 billion.

- Pickering Unit 1 was slated to cost $210 million and ultimately ended up costing $1.00 billion.

However, the figure presented by the FAO for Unit 1 doesn't align with that provided by Ontario Energy Minister, Dwight Duncan, who indicated that Pickering Unit 1 would cost $900 million, putting the completed project much closer to budget.{{Cite web |date=2004-07-26 |title=Ontario government gives thumbs up to Pickering A1 restart |url=https://www.neimagazine.com/news/newsontario-government-gives-thumbs-up-to-pickering-a1-restart |url-status=live |archive-url=https://web.archive.org/web/20200905081806/https://www.neimagazine.com/news/newsontario-government-gives-thumbs-up-to-pickering-a1-restart |archive-date=2020-09-05 |access-date=2022-06-08 |website=Nuclear Engineering International}} This is supported by OPG stating that the project was completed on time and on budget.

The used nuclear fuel and some refurbishment waste generated by the plant sits on-site at the Pickering Waste Management Facility. All operational low and intermediate-level waste is transported to OPG's Western Waste Management Facility at the Bruce nuclear site near Kincardine, Ontario. OPG has proposed the construction and operation of a deep geologic repository for the long-term storage of low and intermediate level waste on lands adjacent to the Western Waste Management Facility.{{cite web |title=Deep Geologic Repository |url=http://www.opg.com/dgr |access-date=2011-04-11 |website=OPG}} The Nuclear Waste Management Organization is currently seeking a site for a potential repository for the used fuel from all Canadian nuclear reactors.

On October 7, 1994, Pickering Unit 7 set the world record for continuous runtime at 894 days, a record that stood for 22 years. It was surpassed by Heysham 2 unit 8 in 2016, a facility located in the UK, owned by EDF.{{cite web |last=Larson |first=Aaron |date=2016-09-21 |title=New Record: Nuclear Power Plant Online for 940 Continuous Days |url=https://www.powermag.com/new-record-nuclear-power-plant-online-for-940-continuous-days/ |url-status=live |archive-url=https://web.archive.org/web/20211009103210/https://www.powermag.com/new-record-nuclear-power-plant-online-for-940-continuous-days/ |archive-date=2021-10-09 |access-date=2021-11-29 |website=PowerMagazine}} This was subsequently surpassed by OPG's Darlington plant with Unit 1 running 1,106 consecutive days.{{cite web |date=2021-02-05 |title=Darlington's Unit 1 heads into planned outage after record-breaking run |url=https://www.opg.com/story/darlingtons-unit-1-heads-into-planned-outage-after-record-breaking-run/ |url-status=live |archive-url=https://web.archive.org/web/20220113234448/https://www.opg.com/story/darlingtons-unit-1-heads-into-planned-outage-after-record-breaking-run/ |archive-date=2022-01-13 |access-date=2022-01-13 |website=OPG}}

- In 2019, Pickering set a site capacity factor record of 87.07%, producing 23.6TWh and putting it roughly on-par with the much newer Darlington and Bruce facilities.

- On May 19th, 2025, the Pickering B units pushed the lifetime production of the Pickering facility over the 1PWh threshold. It joins Bruce in having reached this milestone.

In January 2016, the Province of Ontario approved plans to pursue continued operation of the Pickering Nuclear Generating Station to 2024.{{Cite web |date=2016-01-11 |title=Ontario Moving Forward with Nuclear Refurbishment at Darlington and Pursuing Continued Operations at Pickering to 2024 |url=https://news.ontario.ca/mei/en/2016/01/ontario-moving-forward-with-nuclear-refurbishment-at-darlington-and-pursuing-continued-operations-at.html |url-status=dead |archive-url=https://web.archive.org/web/20160414164800/https://news.ontario.ca/mei/en/2016/01/ontario-moving-forward-with-nuclear-refurbishment-at-darlington-and-pursuing-continued-operations-at.html |archive-date=2016-04-14 |access-date= |website=news.ontario.ca}} The extension was intended to ensure sufficient base load electricity was available during refurbishment of the Darlington Nuclear Generating Station and the initial Bruce Nuclear refurbishments.{{cite web |title=Ontario's Long-Term Energy Plan |url=http://www.energy.gov.on.ca/en/ltep/ |url-status=dead |archive-url=https://web.archive.org/web/20160709050743/http://www.energy.gov.on.ca/en/ltep/ |archive-date=2016-07-09 |access-date=2016-06-28 |website=Canada's Ministry of Energy}} By 2016, OPG had begun planning for the end of commercial operations at the generating station, including the potential repurposing of the Pickering site location.{{Cite web |date= |title=Repurposing Pickering |url=http://www.opg.com/generating-power/nuclear/stations/pickering-nuclear/repurposingpickering/Pages/RepurposingPickering.aspx |url-status=dead |archive-url=https://web.archive.org/web/20160718222607/http://www.opg.com/generating-power/nuclear/stations/pickering-nuclear/repurposingpickering/Pages/RepurposingPickering.aspx |archive-date=2016-07-18 |access-date= |website=Ontario Power Generation}}

OPG will begin the longer term decommissioning process if refurbishment is not pursued. The first step in the long-term decommissioning process is to layup the reactors and place them into safe storage. Pickering staff will have future employment opportunities placing the Pickering units in a safe storage state, at the Darlington refurbishment and operations, or at the potential new build at Darlington.

In September 2022, the Province of Ontario announced that it supported an extension of Pickering's operation from 2024 to 2026. Simultaneously, it announced that it had requested OPG to update feasibility studies on the potential refurbishment of the four units of Pickering B. In its announcement, the Province stated that continued operation of the station would reduce carbon dioxide emissions by 2.1 megatonnes in 2026, as well as increasing the North American supply of cobalt-60, a medical isotope.{{Cite web |title=Ontario Newsroom |url=https://news.ontario.ca/en/release/1002338/ontario-supports-plan-to-safely-continue-operating-the-pickering-nuclear-generating-station |access-date=2023-05-02 |website=news.ontario.ca}}{{Cite web |last=Jones |first=Allison |date=2022-09-29 |title=Ontario plans to extend life of Pickering nuclear plant, eyes refurbishment |url=https://www.cbc.ca/news/canada/toronto/picking-nuclear-extension-ontario-1.6600102 |url-status=live |archive-url=https://web.archive.org/web/20230102080729/https://www.cbc.ca/news/canada/toronto/picking-nuclear-extension-ontario-1.6600102 |archive-date=2023-01-02 |access-date=2023-05-01 |website=CBC News}}

In August 2023, the OPG Board of Directors agreed with and authorized the submission of the feasibility assessment for the refurbishment of the Pickering B plant to the province as well as to proceed with preliminary planning and preparation activities for the project.{{Cite web |date=2023-08-11 |title=OPG REPORTS 2023 SECOND QUARTER FINANCIAL RESULTS |url=https://www.opg.com/documents/2023-second-quarter-financial-results-pdf |url-status=live |archive-url=https://web.archive.org/web/20230820210626/https://www.opg.com/documents/2023-second-quarter-financial-results-pdf |archive-date=2023-08-20 |access-date=2023-08-20 |website=OPG}} This feasibility report was given to the Minister of Energy in January 2024 but was not released to the public because it could harm the "economic or other interests of Ontario.”{{Cite web |last=McClearn |first=Matthew |date=January 21, 2024 |title=Ontario is about to decide whether to overhaul Canada's oldest nuclear power plant. Does it deserve a second life? |url=https://www.theglobeandmail.com/business/article-pickering-nuclear-station-extension-deadline/ |access-date=January 30, 2024 |website=Globe and Mail}}

On January 30, 2024, the Minister of Energy, Todd Smith, announced that the Government of Ontario would be investing in the refurbishment of the four Pickering B reactors that date back to the early 1980s.{{Cite web |last=Crawley |first=Mike |date=January 30, 2024 |title=Doug Ford government to announce plans to refurbish Pickering nuclear plant |url=https://www.cbc.ca/news/canada/toronto/ontario-nuclear-power-pickering-refurbishment-electricity-1.7098524 |website=CBC News}} The refurbishment is expected to be complete by the mid 2030s and should extend the life of the plant by at least another 30 years.{{Cite web |date=2024-01-30 |title=Pickering nuclear plant expected to be fully refurbished by mid-2030s |url=https://www.cbc.ca/player/play/2304845891556 |website=CBC News}}

On October 1, 2024 at 11PM, Pickering 1 was removed from service as planned, as part of the A plant shutdown process.{{Cite web | date=2024-10-01 | title=Unit 1 at Pickering Nuclear removed from service after more than 50 years of production |url=https://durham.insauga.com/unit-1-at-pickering-nuclear-removed-from-service-after-more-than-50-years-of-production/ |website=In Sauga}}

On December 31, 2024 at 12PM, Pickering 4 was removed from service, the final step in the A plant shutdown process.{{Cite web | date=2024-12-31 | title=Unit 4 at Pickering Nuclear A plant officially retired |url=https://durham.insauga.com/unit-4-at-pickering-nuclear-a-plant-officially-retired/ |website=In Sauga}}

A serious incident occurred on August 1, 1983. Pressure tube G16 in the Pickering A Unit 2 reactor developed a 2-metre-long split. The reactor was safely shut down and the damage investigated. The cause was found to be the mis-location of annulus gas spacer springs which allowed the hot pressure tube to sag and touch the inside of the cold calandria tube leading to hydrogen enrichment of the cooler areas. This created a series of small cracks which linked up and caused the long rupture. There was some local fuel damage and the reactor was safely shut down by the operators with no increase in radioactive emissions. The eventual resolution was Large Scale Fuel Channel Replacement and all the pressure tubes were replaced in all Pickering A reactors. The new pressure tubes were supported by an improved design of the annulus gas spacer springs. Since then, careful monitoring of the location of the annulus gas spacer rings has been a significant part of routine reactor inspections.{{Cite web |url=http://www.oocities.org/uoit_psgp/pro/tr.pdf |title=EXAMINATION OF THE PRESSURE TUBE RUPTURE AT PICKERING NGS 'A' UNIT 2, FUEL CHANNEL G16 |access-date=2013-07-21 |archive-date=2013-10-05 |archive-url=https://web.archive.org/web/20131005004826/http://www.oocities.org/uoit_psgp/pro/tr.pdf |url-status=live }}

On December 10, 1994, there was a loss of coolant accident. It is said to be the most serious accident in Canadian history (June 2001) by The Standing Senate Committee on Energy, the Environment and Natural Resources. The Emergency Core Cooling System was used to prevent a meltdown.[http://www.cnp.ca/issues/nuc-threat-mediterranean.pdf "Nuclear Threat in the Eastern Mediterranean" David H. Martin, June 2000, Page 10 (or page 17 of 106)] {{webarchive|url=https://web.archive.org/web/20141013212132/http://www.cnp.ca/issues/nuc-threat-mediterranean.pdf |date=2014-10-13 }}{{Cite web |url=https://sencanada.ca/content/sen/Committee/371/pdf/interim-enrg-e.pdf |title="Pickering A Shutdown and Rehabilitation: A Brief History" page 4 (or page 11 of 51) |access-date=2019-02-03 |archive-date=2019-02-03 |archive-url=https://web.archive.org/web/20190203090911/https://sencanada.ca/content/sen/Committee/371/pdf/interim-enrg-e.pdf |url-status=live }}

In 1995 and 1996, the AECB noted many safety concerns with the plant, and the generating station was shut in 1997 after peer reviews describing poor safety practices at the plant became public. An Independent, Integrated Performance Assessment report noted that Pickering stations A and B were cited for breaking regulation 15 times and having 13 fires for the year. "Also of concern was the high failure rate of persons being tested for positions as nuclear operators. At Pickering A only 65% of those taking the test passed, while at Pickering B the rate was just 56%."{{Cite web |last=Government of Canada |first=Public Services and Procurement Canada |date=2002-07-01 |title=Nuclear power systems : their safety / Lynne C. Myers.: YM32-1/83-14-1999-11E-PDF - Government of Canada Publications - Canada.ca |url=https://publications.gc.ca/site/eng/9.561667/publication.html |access-date=2024-01-31 |website=publications.gc.ca}}

On March 14, 2011, there was a leak of 73 cubic metres of demineralized water into Lake Ontario from a failed pump seal. There was negligible risk to the public according to the Canadian Nuclear Safety Commission.{{Cite web |url=https://www.cbc.ca/news/canada/toronto/pickering-nuclear-plant-reports-water-leak-1.1096682 |title=Pickering Nuclear plant reports water leak, CBC News, March 16 2011 |access-date=2012-04-25 |archive-date=2012-04-30 |archive-url=https://web.archive.org/web/20120430052837/http://www.cbc.ca/news/canada/toronto/story/2011/03/16/pickering-nuclear-leak.html |url-status=live }}

{{Main|Alert Ready#False alarms}}

On January 12, 2020 at 7:24 a.m. ET, an emergency alert was issued via Alert Ready on all radio stations, television stations, television providers, and wireless networks in the province of Ontario, containing an advisory of an unspecified "incident" that had been reported and was being addressed at the plant. The alert stated that no immediate action was required for those within {{convert|10|km|mi}} of the plant. Approximately 40 minutes later, OPG issued a statement via Twitter that the alert had been sent in error, and a second emergency alert was issued at around 9:10 a.m. with a similar message cancelling the previous alert.{{cite news|url=https://www.cbc.ca/news/canada/toronto/pickering-nuclear-generating-station-1.5424115|title=Ontario government apologizes for alert about Pickering nuclear plant incident sent 'in error'|date=2020-01-12|website=CBC News|access-date=2020-01-12|archive-date=2020-01-12|archive-url=https://web.archive.org/web/20200112125921/https://www.cbc.ca/news/canada/toronto/pickering-nuclear-generating-station-1.5424115|url-status=live}}{{cite web|url=https://globalnews.ca/news/6400665/pickering-nuclear-generating-station-emergency-alert/|title=Pickering Nuclear Generating Station emergency alert issued in error, OPG says|website=Global News|language=en|access-date=2020-01-12|archive-date=2020-01-12|archive-url=https://web.archive.org/web/20200112124740/https://globalnews.ca/news/6400665/pickering-nuclear-generating-station-emergency-alert/|url-status=live}}

Solicitor General Sylvia Jones stated that the alert was accidentally issued during a "routine training exercise" by Ontario's emergency operations centre. The incident prompted criticism from government officials, including MPP Peter Tabuns, Pickering mayor Dave Ryan, and Toronto mayor John Tory.{{cite news|url=https://www.nytimes.com/2020/01/12/world/canada/ontario-nuclear-pickering.html|title=Ontario Warned of a Nuclear 'Emergency,' Then Said Never Mind|last=Austen|first=Ian|date=2020-01-12|work=The New York Times|access-date=2020-01-12|language=en-US|issn=0362-4331|archive-date=2020-01-12|archive-url=https://web.archive.org/web/20200112165021/https://www.nytimes.com/2020/01/12/world/canada/ontario-nuclear-pickering.html|url-status=live}}

The false alarm also prompted renewed interest in preparedness for actual nuclear accidents: OPG reported a surge in the sales of potassium iodide kits via its "Prepare to Be Safe" website between January 12 and 13, increasing from its monthly average of 100–200 to over 32,000. The website is applicable for those who live within {{Convert|50|km|mi|abbr=}} of the plant; per Canadian Nuclear Safety Commission (CNSC) requirements, OPG is required to distribute these pills to all residences within {{convert|10|km|mi}} of a nuclear facility.{{cite news|url=https://www.thestar.com/life/health_wellness/opinion/2020/01/20/why-doesnt-everyone-have-ki-pills.html|title=Iodide pills protect you in a nuclear disaster. So, why didn't more people have them before the Pickering scare?|website=Toronto Star|date=20 January 2020|language=en|access-date=2020-01-21|archive-date=2020-01-20|archive-url=https://web.archive.org/web/20200120234507/https://www.thestar.com/life/health_wellness/opinion/2020/01/20/why-doesnt-everyone-have-ki-pills.html|url-status=live}}{{cite news|url=https://www.thestar.com/news/gta/2020/01/14/orders-for-potassium-iodide-pills-surge-after-false-alarm-at-pickering-nuclear-power-plant.html|title=Orders for potassium iodide pills surge after false alarm at Pickering nuclear power plant|website=Toronto Star|date=14 January 2020|language=en|access-date=2020-01-21|archive-date=2020-01-15|archive-url=https://web.archive.org/web/20200115180420/https://www.thestar.com/news/gta/2020/01/14/orders-for-potassium-iodide-pills-surge-after-false-alarm-at-pickering-nuclear-power-plant.html|url-status=live}}{{cite news|url=https://www.cbc.ca/news/canada/toronto/potassium-iodide-pills-nuclear-power-plant-pickering-1.5426044|title=Over 32,000 potassium iodide pills ordered in 2 days after Pickering nuclear power plant alert error|date=January 14, 2020|website=CBC News|access-date=January 20, 2020|archive-date=January 16, 2020|archive-url=https://web.archive.org/web/20200116135515/https://www.cbc.ca/news/canada/toronto/potassium-iodide-pills-nuclear-power-plant-pickering-1.5426044|url-status=live}}

{{Portal|Ontario|Energy|Nuclear technology}}

• List of largest power stations in Canada
• List of commercial nuclear reactors in Canada
• Nuclear power in Canada
• Darlington Nuclear Generating Station
• Bruce Nuclear Generating Station
• Point Lepreau Nuclear Generating Station
• Fitzpatrick Nuclear Generating Station
• Nine Mile Point Nuclear Generating Station
• Frenchman's Bay

{{Reflist|2}}

{{Commons category|Pickering Nuclear Generating Station}}

• [http://www.opg.com/generating-power/nuclear/stations/pickering-nuclear/Pages/pickering-nuclear.aspx Ontario Power Generation]
• [http://maps.google.ca/maps?ll=43.811760,-79.066072&spn=0.020385,0.031672&t=k&hl=en&q=43.811760,-79.066072%20(Pickering%20Nuclear%20Generating%20Station) Google maps satellite image]

{{Nuclear power in Canada}}

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Category:Nuclear power stations in Ontario

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